//! Browser-specific WASM API for Sharenet Passport
//!
//! This module provides browser-compatible functions that work with in-memory data
//! and return encrypted data as bytes. The library is purely in-memory and does not
//! handle any I/O operations - the consumer must handle storage/retrieval.

use wasm_bindgen::prelude::*;
use crate::application::use_cases::{
    SignCardUseCase,
};
use crate::infrastructure::{
    Bip39MnemonicGenerator,
    Ed25519KeyDeriver,
    XChaCha20FileEncryptor,
};
use crate::domain::entities::{Passport, UserIdentity, UserPreferences, PassportFile, RecoveryPhrase, UserProfile};
use crate::domain::traits::{MnemonicGenerator, KeyDeriver, FileEncryptor};

/// Create a new passport with the given universe ID and password
///
/// Returns a JSON string containing both the passport and recovery phrase
/// This function works entirely in memory and doesn't write to any storage.
#[wasm_bindgen]
pub fn create_passport(
    univ_id: String,
    _password: String,
) -> Result<JsValue, JsValue> {
    // For WASM, we need to create a passport in memory without file operations
    // This is a simplified version that creates the passport structure directly
    let generator = Bip39MnemonicGenerator;
    let key_deriver = Ed25519KeyDeriver;

    match generator.generate() {
        Ok(recovery_phrase) => {
            match key_deriver.derive_from_mnemonic(&recovery_phrase, &univ_id) {
                Ok(seed) => {
                    // Derive keys from seed
                    let (public_key, private_key) = key_deriver.derive_from_seed(&seed)
                        .map_err(|e| JsValue::from_str(&format!("Error deriving keys from seed: {}", e)))?;

                    // Create passport with default user profile
                    let passport = Passport::new(
                        seed,
                        public_key,
                        private_key,
                        univ_id,
                    );

                    let result = serde_wasm_bindgen::to_value(&serde_json::json!({
                        "passport": passport,
                        "recovery_phrase": recovery_phrase
                    })).map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
                    Ok(result)
                }
                Err(e) => Err(JsValue::from_str(&format!("Error deriving keys: {}", e))),
            }
        }
        Err(e) => Err(JsValue::from_str(&format!("Error generating recovery phrase: {}", e))),
    }
}

/// Import a passport from recovery phrase
/// Returns the imported passport as JSON
#[wasm_bindgen]
pub fn import_from_recovery(
    univ_id: String,
    recovery_words: Vec<String>,
    _password: String,
) -> Result<JsValue, JsValue> {
    let generator = Bip39MnemonicGenerator;
    let key_deriver = Ed25519KeyDeriver;

    // Validate recovery phrase
    if let Err(_) = generator.validate(&recovery_words) {
        return Err(JsValue::from_str("Invalid recovery phrase"));
    }

    // Reconstruct recovery phrase from words
    let recovery_phrase = RecoveryPhrase::new(recovery_words);

    // Derive keys from recovery phrase
    match key_deriver.derive_from_mnemonic(&recovery_phrase, &univ_id) {
        Ok(seed) => {
            // Derive keys from seed
            let (public_key, private_key) = key_deriver.derive_from_seed(&seed)
                .map_err(|e| JsValue::from_str(&format!("Error deriving keys from seed: {}", e)))?;

            // Create passport with default user profile
            let passport = Passport::new(
                seed,
                public_key,
                private_key,
                univ_id,
            );

            let result = serde_wasm_bindgen::to_value(&passport)
                .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
            Ok(result)
        }
        Err(e) => Err(JsValue::from_str(&format!("Error deriving keys: {}", e))),
    }
}

/// Load a passport from encrypted data (ArrayBuffer/Blob)
/// This accepts encrypted passport data as bytes and returns the decrypted passport
#[wasm_bindgen]
pub fn import_from_encrypted_data(
    encrypted_data: Vec<u8>,
    password: String,
) -> Result<JsValue, JsValue> {
    // Deserialize the encrypted passport file
    let passport_file: PassportFile = serde_cbor::from_slice(&encrypted_data)
        .map_err(|e| JsValue::from_str(&format!("Failed to deserialize passport file: {}", e)))?;

    // Decrypt the passport file using the password
    let encryptor = XChaCha20FileEncryptor;
    let (seed, public_key, private_key, _user_profiles) = encryptor.decrypt(
        &passport_file,
        &password,
    ).map_err(|e| JsValue::from_str(&format!("Failed to decrypt passport: {}", e)))?;

    // Create passport
    let passport = Passport::new(
        seed,
        public_key,
        private_key,
        passport_file.univ_id,
    );

    let result = serde_wasm_bindgen::to_value(&passport)
        .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
    Ok(result)
}

/// Export a passport to encrypted data (ArrayBuffer/Blob)
/// This returns encrypted passport data as bytes that can be downloaded or stored
#[wasm_bindgen]
pub fn export_to_encrypted_data(
    passport_json: JsValue,
    password: String,
) -> Result<Vec<u8>, JsValue> {
    let passport: Passport = serde_wasm_bindgen::from_value(passport_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let encryptor = XChaCha20FileEncryptor;

    // Encrypt the passport data
    let passport_file = encryptor.encrypt(
        &passport.seed,
        &password,
        &passport.public_key,
        &passport.did,
        &passport.univ_id,
        &passport.user_profiles,
    ).map_err(|e| JsValue::from_str(&format!("Failed to encrypt passport: {}", e)))?;

    // Serialize to bytes for browser download
    serde_cbor::to_vec(&passport_file)
        .map_err(|e| JsValue::from_str(&format!("Failed to serialize passport file: {}", e)))
}

/// Sign a message with the passport's private key
#[wasm_bindgen]
pub fn sign_message(
    passport_json: JsValue,
    message: String,
) -> Result<Vec<u8>, JsValue> {
    let passport: Passport = serde_wasm_bindgen::from_value(passport_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let use_case = SignCardUseCase::new();

    match use_case.execute(&passport, &message) {
        Ok(signature) => Ok(signature),
        Err(e) => Err(JsValue::from_str(&format!("Error signing message: {}", e))),
    }
}

/// Generate a new recovery phrase
#[wasm_bindgen]
pub fn generate_recovery_phrase() -> Result<JsValue, JsValue> {
    let generator = Bip39MnemonicGenerator;

    match generator.generate() {
        Ok(recovery_phrase) => {
            let result = serde_wasm_bindgen::to_value(&recovery_phrase)
                .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
            Ok(result)
        }
        Err(e) => Err(JsValue::from_str(&format!("Error generating recovery phrase: {}", e))),
    }
}

/// Validate a recovery phrase
#[wasm_bindgen]
pub fn validate_recovery_phrase(recovery_words: Vec<String>) -> Result<bool, JsValue> {
    let generator = Bip39MnemonicGenerator;

    match generator.validate(&recovery_words) {
        Ok(()) => Ok(true),
        Err(_) => Ok(false),
    }
}

/// Create a new user profile for a passport
/// Returns the updated passport as JSON
#[wasm_bindgen]
pub fn create_user_profile(
    passport_json: JsValue,
    hub_did: Option<String>,
    identity_json: JsValue,
    preferences_json: JsValue,
) -> Result<JsValue, JsValue> {
    let mut passport: Passport = serde_wasm_bindgen::from_value(passport_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let identity: UserIdentity = serde_wasm_bindgen::from_value(identity_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let preferences: UserPreferences = serde_wasm_bindgen::from_value(preferences_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    // Create new user profile and add to passport (in-memory operation)
    let profile = UserProfile::new(hub_did, identity, preferences);
    passport.add_user_profile(profile)
        .map_err(|e| JsValue::from_str(&format!("Error adding user profile: {}", e)))?;

    let result = serde_wasm_bindgen::to_value(&passport)
        .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
    Ok(result)
}

/// Update an existing user profile
/// Returns the updated passport as JSON
#[wasm_bindgen]
pub fn update_user_profile(
    passport_json: JsValue,
    profile_id: String,
    identity_json: JsValue,
    preferences_json: JsValue,
) -> Result<JsValue, JsValue> {
    let mut passport: Passport = serde_wasm_bindgen::from_value(passport_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let identity: UserIdentity = serde_wasm_bindgen::from_value(identity_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    let preferences: UserPreferences = serde_wasm_bindgen::from_value(preferences_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    // Update user profile directly in passport (in-memory operation)
    let profile = UserProfile::new(None, identity, preferences);
    passport.update_user_profile_by_id(&profile_id, profile)
        .map_err(|e| JsValue::from_str(&format!("Error updating user profile: {}", e)))?;

    let result = serde_wasm_bindgen::to_value(&passport)
        .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
    Ok(result)
}

/// Delete a user profile
/// Returns the updated passport as JSON
#[wasm_bindgen]
pub fn delete_user_profile(
    passport_json: JsValue,
    profile_id: String,
) -> Result<JsValue, JsValue> {
    let mut passport: Passport = serde_wasm_bindgen::from_value(passport_json)
        .map_err(|e| JsValue::from_str(&format!("Deserialization error: {}", e)))?;

    // Delete user profile directly from passport (in-memory operation)
    passport.remove_user_profile_by_id(&profile_id)
        .map_err(|e| JsValue::from_str(&format!("Error deleting user profile: {}", e)))?;

    let result = serde_wasm_bindgen::to_value(&passport)
        .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
    Ok(result)
}

/// Change passport password
/// Returns the updated passport as JSON
#[wasm_bindgen]
pub fn change_passport_password(
    _passport_json: JsValue,
    _old_password: String,
    _new_password: String,
) -> Result<JsValue, JsValue> {
    // Note: This function requires re-encryption which typically needs file operations
    // In a browser environment, you'd need to handle this differently
    // For now, we'll return an error indicating this operation isn't supported
    Err(JsValue::from_str(
        "Password change requires file operations which are not supported in browser environment. "
    ))
}

/// Get passport metadata from encrypted data
/// This can extract public metadata without full decryption
#[wasm_bindgen]
pub fn get_passport_metadata(
    encrypted_data: Vec<u8>,
) -> Result<JsValue, JsValue> {
    // Deserialize the encrypted passport file
    let passport_file: PassportFile = serde_cbor::from_slice(&encrypted_data)
        .map_err(|e| JsValue::from_str(&format!("Failed to deserialize passport file: {}", e)))?;

    let metadata = serde_json::json!({
        "did": passport_file.did,
        "univ_id": passport_file.univ_id,
        "public_key": hex::encode(&passport_file.public_key),
        "created_at": passport_file.created_at,
        "version": passport_file.version,
    });

    let result = serde_wasm_bindgen::to_value(&metadata)
        .map_err(|e| JsValue::from_str(&format!("Serialization error: {}", e)))?;
    Ok(result)
}

/// Validate passport file integrity from encrypted data
#[wasm_bindgen]
pub fn validate_passport_file(
    encrypted_data: Vec<u8>,
) -> Result<bool, JsValue> {
    match serde_cbor::from_slice::<PassportFile>(&encrypted_data) {
        Ok(passport_file) => {
            // Basic validation checks
            let is_valid = !passport_file.enc_seed.is_empty()
                && !passport_file.salt.is_empty()
                && !passport_file.nonce.is_empty()
                && !passport_file.public_key.is_empty()
                && !passport_file.did.is_empty()
                && !passport_file.univ_id.is_empty();

            Ok(is_valid)
        }
        Err(_) => Ok(false),
    }
}